Fleet UI: Update report and policies empty states

[RachelElysia]

Issue

Closes #35483

Description

• Updates empty states of reports and policies pages only

Testing

• Added/updated automated tests
• QA'd all new/changed functionality manually

[codecov]

Codecov Report

❌ Patch coverage is 87.50000% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 66.78%. Comparing base (d2033df) to head (70f8bd5).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...ies/details/components/QueryReport/QueryReport.tsx	0.00%	2 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #45064   +/-   ##
=======================================
  Coverage   66.78%   66.78%           
=======================================
  Files        2718     2719    +1     
  Lines      218769   218810   +41     
  Branches    10745    10764   +19     
=======================================
+ Hits       146109   146137   +28     
- Misses      59496    59510   +14     
+ Partials    13164    13163    -1     

Flag	Coverage Δ
frontend	55.32% <87.50%> (+0.01%)	⬆️

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